N-sec-alkyl-2,6-dinitro-3,4-xylidine herbicides

ABSTRACT

This invention relates to certain novel substituted 2,6dinitroaniline compounds, which are useful as herbicides.

United States Patent 1191 Lutz et al. Nov. 18, 1975 [5 1N-SEC-ALKYL:2,6-DlNlTRO-3,4-XYLIDINE 3,332,769 7/1967 Soper 260/577 xHERBICIDES 3.764.623 10/1973 Hunter et a1 260/577 x 3.764.624 10/1973Strong et a1. 260/577 x [75] Inventors: Albert William Lutz, MontgomeryTownship, Somerset County; Robert Eugene Diehl, Trenton, both of NJ.

[73] Assignce: American Cyanamid Company,

Stamford, Conn.

122 Filed; Jan.12, 1973 21 Appl. No.: 323,000

' Related US. Application Data [63] Continuation-impart of Ser. No.262,807, June 14,

1972. abandoned. which is a continuation-in-part of Ser. No. 174,938.Aug. 25. 1971, abandoned.

[52] US. Cl. 260/577; 71/88; 71/95; 71/98; 71/105; 71/121; 260/247;260/247.1

R; 260/2475 R; 260/247.7 C; 260/293.72; 260/293,73; 260/293.75;260/293.79;

260/326.85; 260/465 E; 260/556 AR;

[51] Int. Cl. C07C 87/62; CO7C 93/14 [58] Field of Search 260/577 [56]References Cited UNITED STATES PATENTS 3.257.190 6/1966 Soper 260/577 XOTHER PUBLICATIONS l-lemmerich, Chem. Abstracts, Vol. 52, p. 20183a(1958).

Woods et a1., Chem. Abstracts, Vol. 75, p. 456, abstract No.35386f(1971).

Abrahamsson et a1., Chem. Abstracts, Vol. 66, p. 10208, abstract No.109220K (1967).

Deorha et al., J. Indian Chem. Soc., Vol. 40 (10), pp. 894-896 (1963).

Crossley et al., J. Chem. Soc., Vol. 103 pp. 982-989 (1913).

Primary ExaminerLewis Gotts Assistant E.\'aminerS. P. Williams Attorney,Agent, or Firm-Robert P. Raymond [57] ABSTRACT This invention relates tocertain novel substituted 2,6- dinitroaniline compounds, which areuseful as herbicides.

5 Claims, No Drawings N-SEC-ALKYL-2,6-DINlTRO-3,4-XYLIDINE HERBICIDESThis application is a continuation-in-part application Ser. No. 262,807,filed June 14, 1972, which is in turn a continuation-in-part ofapplication Ser. No. 174,938, filed Aug. 25, 1971, both now abandoned.

This invention relates to certain novel substituted 2,6-dinitroanilinecompounds.

The novel 2,6-dinitroaniline compounds of the present invention may berepresented by the following structural formula:

wherein, R represents l-ethylbutyl; l-ethylpropyl; lmethylpropyl orlmethylbutyl.

The above-identified compounds are highly effective herbicidal agents.

The herbicidal methods comprise application of a herbicidally effectiveamount of one or more compounds of Formula I to the soil containing theseeds of undesirable plant species to be controlled.

Wherein an asymmetric carbon atom exists in the di nitroanilinecompounds above, optical isomerism may exist. Accordingly, suchcompounds may be employed as separate antimers or in admixture, as in aracemic composition. Unless there is indication to the contrary byreference to such a compound, the unresolved composition is intendedherein. Separation of antimers, where desired, may be effected byconvention resolution techniques. A convenient method relates to theintroduction of an optically active substituent, such as a()-sec-butylamino group into the ring system, as by nucleophilicsubstitution, as exemplified below.

Preferably, application of these compounds, or active ingredients ismade using the herbicidal compositions described below with conventionalapplication methods.

The 2,6-dinitroaniline compounds are prepared by a nucleophilicsubstitution of a l-substituent, such as, a chloro group, with theappropriately substituted amine. While chloro is a preferredsubstituent, and the discussion is in terms thereof other conventionalequivalent substituents, such as, brorno or iodo are included herein.The displacement may be conducted with or without an organic solvent,such as toluene, benzene or preferably xylene.

The reaction, which is graphically illustrated below, is carried out byheating the reactants, preferably between 50 and 150C.

Cl O N N 0 N RNH2 xyleneE CH3 (III) A wherein R is as defined above.

The chlorobeiizene intermediate can be prepared by reacting anappropriately substituted aniline with ethyl chloroformate in benzene atabout 10C. to 50C. to yield the correspondingly substitutedN-(ethoxycarbonyl)-3,4-substituted aniline. This product is then treatedwith a cold solution of sulfuric and nitric acid, i.e., at about 0C. to20C. to obtain the N-(ethoxycarbonyl )-3,4-disubstituted-2,-dinitroaniline. Reaction of the thus-formed productwith sulfuric acid at an elevated temperature, preferably between about100C. and 150C., converts the N-(ethoxycarbonyl) product to the3,4-disubstituted-2,o-dinitroaniline. The amino group is replaced by achlorine atom by first heating the compound with glacial acetic acid anddiazotizing the amine with a mixture of sodium nitrite in sulfuric acid.This is followed by treating the diazotized mixture with a mixture ofcuprous chloride in hydrochloric acid, and then heating the thus-formedmixture to about 40C. to C. to obtain the chlorinated compound.

The preemergence herbicidal compositions are solid or liquidformulations comprising an effective amount of one or more of the2,6-dinitroaniline compounds of Formula I with a herbicidal adjuvant,i.e., an inert carrier or other conventional fonnulation aid.

Preparation of said compositions broadly involves admixing an effectiveamount of the herbicidal agent and adjuvant.

Use of said compositions broadly involves application of an effectiveamount of said compounds or preferably said compositions to the soilcontaining seeds of the plants to be controlled.

Typical formulations include, for example, dusts, dust concentrates,wettable powders, granulars, and the like. Application by conventionalmethods and equipment is usually made at rates of from about oneeighthpound per acre to about 20 pounds per acre and preferably h to 8 poundsper acre of active material.

Dusts are generally prepared by grinding together from about 1% to 15%by weight of the active material with from about 99% to by weight of asolid diluent, such as an attaclay, kaolin, diatomaceous earth, fullersearth, talc, pumice or the like.

Dust concentrates are prepared in similar fashion to the dusts exceptingthat generally about 15% to about by weight of active material is used.

Granular formulations may be prepared by applying liquid solution of theactive material to sorptive granlar carriers, such as attaclay, kaolin,or diatomite ranules. Alternatively, they may be mixed with inertarriers and applied to non-sorptive granules, such as 1nd or limestoneWettable powders are prepared by grinding the acve ingredient with asolid carrier, such as used in the ust formulations. Usually, about 25%to 75% by 'eight of the active material and from about 73% to 3% byweight of solid carrier is used. In addition, there generally addedabout 1% to 5% by weight of a disersing agent, such as alkali metalsalts of naphthalene ilfuric acid and anionic-nonionic blends, and frombout 1% to 5% by weight of a surfactant, such as polyxyethylenealcohols, acids, adducts, sorbitan fatty :id esters and sorbitol esters.Typical formulations be eight percent are given below.

TABLE I The wettable powder formulations are usually disersed in waterand applied as a liquid spray to the area r locus where control ofundesirable plant species is esired.

For use as preemergence herbicides, the dusts or liqld sprays containingthe active compound can be apied to the soil shortly after planting orthey may be \corporated into the soil by the technique referred topreplant incorporation.

The practice and advantages of the present invention id preparation ofthe active ingredients used therein is lrther illustrated by thefollowing examples which are )t to be takenas being limitative thereof.Parts and :rcentages herein are by weight unless otherwise indilted.

EXAMPLE 1 reparation of 3,4-Dimethyl-2,6-dinitrochlorobenzene Two gramsof 3,4-dimethyl-2,-dinitroaniline [Chemal Abstracts 44: 4447 1950)] isdissolved in 40 ml. of arm glacial acetic acid. The solution is cooledto om temperature and a mixture of 0.9 grams of soum nitrate in 7 ml. ofconcentrated sulfuric acid is lded very slowly leaving a solid in themixture. This ixture is then added to a solution of cuprous chlorideconcentrated hydrochloric acid. The cuprous chlo- 1e solution isprepared by dissolving 3.24 grams of uSO .5H O in water and adding NaClto the warm sotion. While holding the blue solution in an ice bath, a'lution of 1.24 grams of sodium meta-bisulfite and 52 grams of NaOH in12 ml. of water is added. A hite precipitate forms and is dissolved in12 ml. of mcentrated hydrochloric acid. The diazonium mixre is thenwarmed, filtered, and the solid collected Id recrystallized fromcyclohexane. The product has a 4 melting point of 109C. to 111C. Theprocedures are repeated using 16 grams of the amine, yielding 11 gramsof product, having a melting point of l 11C. to 113C.

EXAMPLE 2 Preparation of 3,4-Dimethyl-2,6-dinitrochlorobenzene two timeswith 200 ml. xylene and filtered. The filter cake is then washed with 50ml. cold xylene and 300 ml. of methanol at 50C. The solid is thenrecrystallized from 2500 ml. of methanol and washed with 2 pints ofpetroleum ether. The yield of white solid is grams with melting point 112 to l 13C.

EXAMPLE 3 Preparation of N-sec-Butyl-3,4-dimethyl-2,6-dinitroaniline Amixture of 4-chloro-3,5-dinitro-o-xylene grams, 0.61 mole),mono-sec-butylamine (184 ml., 1.82 moles), and xylene (1400 ml.) isbrought to reflux. After refluxing overnight, the reaction mixture iscooled and filtered. The precipitate is washed with petroleum ether. Thefiltrate and washings are combined, washed with 500 ml. of 10%hydrochloric acid, and finally with 2 liters of water. The organic layeris separated and dried. Removal of the drying agent and the solventleaves an orange oil which crystallizes with the addition of petroleumether. A yellow orange solid (150.6 grams, 86.5%) with melting point 42to 43C. is collected.

EXAMPLES 4 to 7 Following the general procedures of Example 3substituting the appropriate amine for the amine used therein, yieldsproducts having the following formula and properties set forth in Table11 below.

TABLE Il-continued Example Substituents Melting Crystallizing NumberPoint Solvent CHCH CH CH 7 1 42-43 methanol EXAMPLE 8 Preparation of()-N-sec-Butyl-2,6-dinitro-3,4-xylidine ()-sec-Butylamine [preparedaccording to L. Verbit and P. J. Heffron, Journal of Organic Chemistry32, 3199 (1967)] was reacted with 4-chloro-3,5-dinitro-oxylene as by thegeneral procedure of Example 3 to give a yellow-orange solid withmelting point 37C. to 38.5C., [01], l.38 (c 2.071, ethanol).Concentrations, abbreviated c herein, are measured in grams per 100 ml.of solution.

EXAMPLES 9 to 10 Preparation of ()-N-[ l-( Methoxymethyl)propyl]-2,6-dinitro-3,4- xylidine ()-2-Amino-l-butanol [100 grams,prepared according to D. Pitre and E. B. Grabitz, Chimia 23, 399 (1969)]was added in a dropwise manner to a stirred solution of tert-butanol(800 ml.) containing potassium tert-butoxide (126 grams). After warmingthis mixture to 70 to 80C. for 2 hours, methyl iodide (175 grams) wasadded slowly at temperatures below 50C. The suspension which formed wasthen stirred with refluxing overnight. After removal of the solid phaseby filtration, the filtrate was fractionally distilled to give ()-l-(methoxymethyl)propylamine contaminated with traces of tert-butanol,boiling point 125C. to l47C./- 760 mm. This amine was then allowed toreact with 4- chloro-3,S-dinitro-o-xylene, as described earlier, to givethe desired product as a bright yellow solid with melting point 42.5C.to 44C., [od l 37.6 (c 2.504, chloroform).

The following optical isomers were also prepared using the appropriateoptically active amine and following essentially the procedure above:

EXAMPLES 11 to 14 The selective preemergence herbicidal activity of thecompounds of the present invention is exemplified by the following testsin which theseeds of a variety of monocotyledonous and dicotyledonousplants are separately mixed with potting soil and planted on top ofapproximately 1 inch of soil in separate pint cups. After planting, thecups are sprayed with the selected aqueous-acetone solution containingtest compound in sufficient quantity to provide the equivalent of about0.25 to 4 pounds per acre of test compound per cup. The treated cups arethen placed on greenhouse benches, watered and cared for in accordancewith conventional greenhouse procedures. Three or four weeks aftertreatment, the tests are terminated and each cup is examined and ratedaccording to the rating system set forth below. The herbicidalproficiency of the active ingredients of the present invention isevident from the test results which are reported in the tables below.

Rating System Difference in Growth Rating System from the Check* butwith an over-all effect less than a 5 on the rating scale.

Based on visual determination of stand size, vigor, chlorosis growthmalformation andover-all plant appearance.

Plant Abbreviations CR Crabgrass VEL Velvet leaf BA Barnyard grass FOXGreen foxtail Pl Pigweed MG Annual Morning-glory LA Lambsquarters COTCotton COR Corn SB Sugarbeets WO Wild oats SOY Soybean TABLE 111 ExampleCompound Melting Number Name Point [01],,

9 (+)N-sec-butyl-2.6-dinitro- 38-385 50.18

3.4-xylidine (c 2.217, ethanol) 10 (-)-N( l-methylbutyl) 59-61 58.0

(c 2.449, ethanol) Test Species LA PI MG BA CR F0 WO -CN CO SY SB VLTABLE V Herbicidai Activity of Optically Active and RacemicDiniu'ouniline Compounds Rate Compound i NH-CH-C We claim: 1. A compoundhaving the structure:

wherein R is l-ethylbutyl, l-ethylpropyl, l-methylpropyl andl-methylbutyl.

2. A compound having the structure:

v H CHCHZCHQCHS 3. A compound having the structure:

I H\N/CHCH2CH3 O N N0 4. A compound having the structure:

I H cucn cn 'Inventor(s) UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 3,920 Dated November 18 1975 Albert William Lutzet al PAGE 1 of 2 It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Columns 7 and 8 TABLE IV should appear as shown on the attached sheet.

Signed and Scaled this twenty-fourth D 3y of February 1 9 76 [SEAL] RUTHC. MASON Arresting Officer C. MARSHALL DANN Commissioner ofParents andTrademarks FORM PO-1050 (10-69) USCOMM-DC 6D376-P69 U.S. GOVERNMENTPRINTIN G OFFICE: 8 69- 93 o

1. A COMPOUND HAVING THE STRUCTURE:
 2. A compound having the structure:3. A compound having the structure:
 4. A compound having the structure:5. A compound having the structure: